If you are going for a replacement the best option is one of the Edelbrock carbs and preferably with a manual choke which I found much better on my 411/3 and on my Range Rover LSE which we recently converted from EFI to Carb.
With the Edelbrock you will also need the kick down conversion kit for the Chrysler engine/gearbox installation which is not expensive and from memory straight forward to fit.
If you do fancy doing a rebuild I attach a link to a US supplier who should be able to sell you the correct rebuild kit for your existing Carb, I have bought parts from him for the Carter on my 603E and they arrived within a week which was excellent, but my preference would be an new Edelbrock.
Geoff.
https://www.carburetor-parts.com/afb...r-rebuild-kits